Chevrolet had optional shocks for the 1.5 ton trucks and were mostly used with a panel trucks that carried light loads; you could get reduced load leaf springs for these vehicles. I have a 1935 1.5 ton stake truck that was bought by the US Forestry Dept and it has 157" wheel base and has overlaod springs in the rear (They were an option) and it has double action optional shocks all the way around. They maybe help a little bit on washboard roads when running light.
